Development of analytic system of brushing strokes and computer assisted instruction system

对刷牙运动进行了三维运动捕捉和运动分析。志愿者的牙刷、脸部、右手、手臂、肩膀和胸部上贴着37个球状的记号笔。使用5个摄像机进行视频图像采集，并使用Ishikawa等人开发的无需摄像机定标的算法对视频图像进行运动恢复。以每秒10帧的间隔记录三种不同技术的30秒刷牙动作。编辑静止帧以生成标记位置的三维曲线图。总共包括322个火焰和11714个标记用于运动分析。生成了“刷丝”模型的三维重建运动图像。这使得可以从各个方向观察到刷牙的运动。此外，还实现了特定标记的顺序移动的提取，以评估它们对笔画的贡献。每个标记物的振幅、速度和加速度可以结合标记物的能量消耗来计算。运动捕捉技术使描述刷牙过程中关节和特定标志物的动力学成为可能。突出显示特定关节的运动将帮助患者认识到他们刷牙动作的任何特点。分析与刷牙笔画相关的特定标记物的特征将有助于对刷牙技能水平和有效的刷牙指导进行批判性评估。

Three-dimensional motion capture and movement analysis was performed on tooth brushing motion. There were 37 ball-shaped markers attached to the toothbrush, face, right hand, arms, shoulders and the chest of the volunteer. Video image capture was performed with 5 video cameras and the video images were processed for the motion recovery using camera calibration free algorithm developed by Ishikawa et al. Thirty seconds of brushing motion with three different techniques were recorded at intervals of 10 frames per second. Still frames were edited to generate three-dimensional plots of the marker positions. In total, 322 flames and 11714 markers were included for the motion analysis. Three-dimensionally reconstructed motion pictures of "brushing" wire-fame model was generated. That allowed observation of the brushing motion from all directions. Further more, extraction of the sequential movement of specific markers was achieved to evaluate their contributions to the brushing strokes. The amplitude, velocity and acceleration of each marker could be calculated using the three-dimensional plots together with energy expenditure of markers. Motion capture technique made it possible to characterize joint and specific marker kinetics during tooth brushing. Highlighted movement of specific joints will help patients realize any peculiarities of their brushing motion. Analysis of characteristics of specific markers related to brushing strokes will help with critical evaluation of the skill levels of the brushing and the effective brushing instruction.